Cardiac rhythm management system having multi-capacitor module

ABSTRACT

A multi-capacitor module carries vertically-oriented surface mount tantalum capacitors. The module provides at least one conductor for coupling to the substrate capacitor terminals that are distal thereto. The module occupies less space, when mounted to a circuit board substrate, than individually mounting the bases of the surface mount capacitors to the substrate. This allows more efficient use of volume within an implantable cardiac rhythm management device, reducing its size, or alternatively, increasing its implanted longevity.

This application is a division of U.S. patent application Ser. No.09/073,581 filed May 6, 1998, now U.S. Pat. No. 6,243,605 (the '581Application). The '581 Application is incorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

This invention relates generally to a multi-capacitor module andparticularly, but not by way of limitation, to its use in a cardiacrhythm management system.

BACKGROUND OF THE INVENTION

Capacitors are electrical components that store electrical energy in anelectromagnetic field between electrodes that are separated by adielectric insulator. Each electrode carries a charge that is oppositein polarity to the charge on the other electrode. Capacitors find manyapplications in a wide variety of electric circuits. For example,implantable defibrillators and pacemakers provide cardiac rhythmmanagement therapy to the heart in the form of low energy pacing pulsesto evoke heart contractions and high energy electrical countershocks tointerrupt certain arrhythmias. Such cardiac rhythm management devicesinclude circuits that sense heart activity and control the delivery oftherapy. Many of these circuits use capacitors. For example, capacitorsare used to store energy for the delivery of low or high energy therapyto the heart. Capacitors are also used to in filter circuits that removeunwanted signals. In another example, capacitors are used to storeenergy for stabilizing power supply circuits.

One goal in designing electronic devices is to reduce the size of theelectronic device, which makes the device more portable. In implantabledevices, size reduction is not just important, it is critical. A smallerdevice is easier for the physician to implant in the patient. Moreover,by reducing the size of other components in an implantable device, alarger battery can be used, prolonging the implanted longevity of thedevice before a replacement device is required. Increasing the implantedlongevity of such devices reduces the cost of the patient's medicaltreatment, which is extremely important in the present environment ofrising medical costs.

Many discrete capacitors used in implantable medical devices are surfacemount devices that are mounted onto multilayer hybrid substrate circuitboards. Unfortunately, such capacitors often consume a large area of thecircuit board. This tends to increase the size of the implantabledevice, or alternatively, tends to reduce implantable longevity byreducing the battery size that can be accommodated in a particular sizedevice. Thus, there is a critical need to more effectively use discretecapacitors in implantable medical devices and other electronic circuits.

SUMMARY OF THE INVENTION

The above-mentioned shortcomings, disadvantages and problems areaddressed by the present invention, which will be understood by readingand studying the following specification and accompanying drawings thatform a part thereof. The present invention provides, among other things,a multi-capacitor module. The module includes a module body havingopposing top,and bottom module surfaces. The module body includingelectrical terminals for connecting to an external circuit. The modulealso includes a plurality of capacitors within the module. Eachcapacitor is electrically coupled to terminals on the module body. Eachcapacitor includes a capacitor body having opposing first and secondcapacitor ends defining a capacitor height therebetween. The firstcapacitor end is adjacent to the bottom module surface. The secondcapacitor end is adjacent to the bottom module surface. One of the firstand second capacitor ends defines a length and a width of the capacitor.The capacitor height is longer than each of the length and the width ofthe capacitor.

In various further embodiments, the module includes capacitors having afirst and second capacitor terminals at respective first and secondcapacitor ends. At least one conductor is electrically coupled to atleast one of the second capacitor terminals (approximately adjacent tothe top module surface). The conductor extends to the bottom surface ofthe module. Each capacitor includes a base extending between the firstand second capacitor ends. The first capacitor terminal extendspartially along the base proximal to the first capacitor end. The secondcapacitor terminal extends partially along the base proximal to thesecond capacitor end.

In various further embodiments, the capacitors are tantalum capacitors(e.g., surface mount tantalum capacitors). The bottom module surface isopen for accessing an interior of the module body. The terminals on themodule body are located on the bottom surface of the module. In oneembodiment, the present invention includes a circuit board having theabove-described module mounted thereupon. In one embodiment, the circuitboard comprises a hybrid circuit board substrate that includes multipleconductive and insulating layers.

Another aspect of the invention provides, among other things, amulti-capacitor module. The module includes a module body havingopposing top and bottom module surfaces. Surrounding side surfacesextend between the top and bottom module surfaces. The top, bottom, andside module surfaces define an interior portion of the moduletherebetween. The module body includes electrical terminals forconnecting to an external circuit. A plurality of tantalum capacitorsare within the module. Each capacitor includes a capacitor body havingopposing first and second capacitor ends defining a capacitor heighttherebetween. One of the first and second capacitor ends defines alength and a width of the capacitor. The capacitor height is longer thaneach of the length and the width of the capacitor. The capacitors arevertically disposed in a row within the module. The first capacitor endsare substantially adjacent to the bottom module surface. The secondcapacitor ends are substantially adjacent to the top module surface.Each capacitor includes a base extending between the first and secondcapacitor ends. A first capacitor terminal is located at the firstcapacitor end. The first capacitor terminal extends partially along thebase proximal to the first capacitor end. A second capacitor terminal islocated at the second capacitor end. The second capacitor terminalextends partially along the base proximal to the second capacitor end. Aconductor is located substantially in the interior portion of themodule. The conductor extends along the interior portion of the topmodule surface. The conductor is electrically coupled to each of thesecond capacitor terminals. The conductor also extends along theinterior portion of one of the side module surfaces, and further extendsto the bottom module surface. The conductor provides an electricalterminal for connecting the second capacitor terminals to an externalcircuit.

In various further embodiments, the present invention also includes acircuit board having the above-described module mounted thereupon at thebottom module surface. The circuit board is electrically coupled to aportion of the conductor at the bottom module surface. The circuit boardis also electrically coupled to the first capacitor terminals at thebottom module surface. In one embodiment, the circuit board comprises ahybrid circuit board substrate that includes multiple conductive andinsulating layers. In a further embodiment, the conductor and the firstcapacitor terminals are soldered to the circuit board. In oneembodiment, the module body includes a notched corner between the topmodule surface and one of the side module surfaces, and five capacitorsare carried within the module.

Another aspect of the invention provides, among other things, a cardiacrhythm management system. The system includes a housing, a batterywithin the housing, and a hybrid circuit board substrate, within thehousing, The substrate includes multiple conductive and insulatinglayers. A multi-capacitor module is mounted to the substrate. Themulti-capacitor module includes a module body having opposing top andbottom module surfaces. The module body includes electrical terminalsthat are electrically coupled to the substrate. The bottom modulesurface is mounted to the substrate. A plurality of capacitors iscarried within the module.

In various further embodiments, the capacitors are surface mounttantalum capacitors. Each capacitor is electrically coupled to terminalson the module body. Each capacitor includes a capacitor body havingopposing first and second capacitor ends defining a capacitor heighttherebetween. One of the first and second capacitor ends defines alength and a width of the capacitor. The first capacitor end isapproximately adjacent to the substrate. The capacitor height is longerthan each of the length and the width of the capacitor. Each capacitorincludes first and second capacitor terminals at the respective firstand second capacitor ends. At least one conductor is electricallycoupled to at least one of the second capacitor terminals. The conductorextends to the bottom surface of the module. The conductor provides oneof the terminals, on the module body, that is electrically coupled tothe substrate.

In various further embodiments, each capacitor includes a base extendingbetween the first and second capacitor ends. The first capacitorterminal extends partially along the base proximal to the firstcapacitor end. The second capacitor terminal extends partially along thebase proximal to the second capacitor end. In one embodiment, the bottommodule surface advantageously occupies less mounting area on the surfaceof the substrate than areas of the bases summed over the plurality ofthe capacitors. In one embodiment, the first capacitor terminals provideterminals, on the module body, that are electrically coupled to thesubstrate. The bottom module surface is open for accessing an interiorof the module body.

Another aspect of the invention provides, among other things, a methodof forming a multi-capacitor module. A module body is formed to includeopposing top and bottom module surfaces, and to include electricalterminals for connecting to an external circuit. A plurality of surfacemount capacitors are disposed within the module. Each capacitor includesa capacitor body having opposing first and second capacitor endsdefining a capacitor height therebetween. One of the first and secondcapacitor ends defining a length and a width of the capacitor. Thecapacitor height is longer than each of the length and the width of thecapacitor.

Another aspect of the invention provides, among other things, a methodof making a cardiac rhythm management system. A housing is formed. Abattery is disposed within the housing. A hybrid circuit boardsubstrate, including multiple conductive and insulating layers, isdisposed within the housing. A multi-capacitor module is mounted on thesubstrate. The module includes a module body having opposing top andbottom module surfaces. A plurality of capacitors is disposed within themodule. In a further embodiment, disposing the plurality of capacitorsincludes disposing a plurality of surface mount tantalum capacitorswithin the module.

Another aspect of the invention provides, among other things, a methodof using a plurality of capacitors. Each capacitor includes opposingfirst and second capacitor ends defined by a capacitor length and acapacitor width. The capacitor includes a base defining a capacitorheight that is longer than each of the capacitor length and width. Thecapacitors are inserted into a multi-capacitor module having opposingtop and bottom module surfaces such that the first capacitor ends areapproximately parallel and proximal to the bottom module surface. Thebottom module surface is open (such as for allowing insertion of thecapacitors). The bottom module surface is mounted to a hybrid circuitboard substrate.

In various further embodiments, the method includes electricallycoupling a terminal on each second capacitor end to the substrate, suchas by contacting the terminal on at least one of the second capacitorends using a conductor and attaching the conductor to the substrate. Inone embodiment, attaching the conductor to the substrate includessoldering the conductor to the substrate. A terminal on each firstcapacitor end is electrically coupled to the substrate. In oneembodiment, electrically coupling the terminals on each first capacitorend to the substrate includes soldering the terminals on each firstcapacitor end to the substrate.

Another aspect of the invention provides, among other things, a methodof mounting surface mount capacitors on a circuit board. Each capacitorincludes a solid rectangular shape that includes a base havingelectrical contacts at opposing ends of the base. A plurality of thecapacitors are inserted vertically into a module having opposing top andbottom module surfaces. The module includes side module surfacesextending between the top and bottom module surfaces. The capacitors areinserted such that the base of the capacitor is parallel to one of theside module surfaces. The electrical contacts at opposing ends of thebase of the capacitor are proximal to the respective top and bottommodule surfaces. The electrical contacts that are proximal to the bottommodule surface are electrically coupled to the board. The electricalcontacts that are proximal to the top module surface are electricallycoupled to the board via a conductor extending therebetween.

In summary, the present invention provides, among other things, amulti-capacitor module for carrying vertically-oriented surface mountcapacitors. The module provides at least one conductor for coupling tothe substrate capacitor terminals that are distal thereto. The moduleoccupies less space, when mounted to a circuit board substrate, thanindividually mounting the bases of the surface mount capacitors to thesubstrate. This allows more efficient use of volume within animplantable cardiac rhythm management device, reducing its size, oralternatively, increasing its implanted longevity. Other advantages willbecome apparent upon reading the following detailed description of theinvention and viewing the accompanying drawings that form a partthereof.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals describe substantially similar componentsthroughout the several views. Shapes and dimensions are not criticalunless indicated as such in the drawing or the accompanying detaileddescription of the invention.

FIG. 1 is a schematic/block diagram illustrating generally oneembodiment of a cardiac rhythm management system.

FIG. 2A is a schematic diagram of a perspective view illustratinggenerally an arrangement of surface mount capacitors on a substrate.

FIG. 2B is a schematic diagram, taken along the cutline 2B—2B of FIG.2A, illustrating generally a cross-sectional view of one embodiment of acapacitor.

FIG. 3A is a schematic diagram illustrating generally an exteriorperspective view of a multi-capacitor module.

FIG. 3B is a schematic diagram illustrating generally a cross-sectionalside view of the multi-capacitor module taken along the cutline 3B—3B inFIG. 3A.

FIG. 3C is a schematic diagram illustrating generally a bottom view ofthe multi-capacitor module taken along the cutline 3C—3C in FIG. 3B.

FIGS. 3D, and 3E are schematic diagrams illustrating generallyparticular configurations of interconnecting the capacitors.

FIG. 4A is a schematic diagram illustrating generally an exteriorperspective view of another embodiment of a multi-capacitor module.

FIG. 4B is a schematic diagram illustrating generally a cross-sectionalside view of the multi-capacitor module taken along the cutline 4B—4B inFIG. 4A.

FIG. 4C is a schematic diagram illustrating generally a bottom view ofthe multi-capacitor module taken along the cutline 4C—4C in FIG. 4B.

FIGS. 4D, 4E, and 4F are schematic diagrams illustrating generallyparticular configurations of interconnecting the capacitors.

FIG. 5A is a schematic diagram of a plan view of surface mountcapacitors having bases mounted directly to a substrate.

FIG. 5B is a schematic diagram of a plan view of surface mountcapacitors that are vertically disposed in a module mounted to thesubstrate.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof, and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it is tobe understood that the embodiments may be combined, or that otherembodiments may be utilized and that structural, logical and electricalchanges may be made without departing from the scope of the presentinvention. The following detailed description is, therefore, not to betaken in a limiting sense, and the scope of the present invention isdefined by the appended claims and their equivalents.

The present invention provides, among other things, a multi-capacitormodule for use in a cardiac rhythm management system or other electricalcircuit. The multi-capacitor module includes surface mount capacitorsthat are arranged to minimize the space occupied on a hybrid circuitboard. This helps reduce the volume of the implantable cardiac rhythmmanagement system or, alternatively, increases its implanted longevity.Other advantages of the present invention will also become apparent byreading the following detailed description of the invention and viewingthe accompanying drawings which form a part thereof,

FIG. 1 is a schematic/block diagram illustrating generally, by way ofexample, but not by way of limitation, one embodiment of a cardiacrhythm management system 100 according to one aspect of the presentinvention. System 100 includes, among other things, cardiac rhythmmanagement device 105 and leadwire (“lead”) 110 for communicatingsignals between device 105 and a portion of a living organism, such as aheart 115. In the illustrated example, device 105 includes an automaticimplantable cardioverter/defibrillator (AICD), but any other apparatusfor cardiac rhythm management is also included within the presentinvention.

In the illustrated embodiment, portions of system 100 is implantable inthe living organism, such as in a pectoral or abdominal region of ahuman patient, or elsewhere. In another embodiment, portions of system100 (e.g., device 105) are alternatively disposed externally to thehuman patient. In the illustrated embodiment, portions of lead 110 aredisposed in the right ventricle, however, any other positioning of lead110 is included within the present invention. In one embodiment, lead110 is a commercially available endocardial defibrillation lead. System100 can also include other leads in addition to lead 110, appropriatelydisposed, such as in or around heart 115, or elsewhere.

In one example, a first conductor of multiconductor lead 110electrically couples a first electrode 120 to device 105. A secondconductor of multiconductor lead 110 independently electrically couplesa second electrode 125 to device 105. Device 105 includes an energysource, such as battery 130, a power converter 135, such as a flybackconverter, at least one defibrillation output capacitor 140, and acontroller 145 for controlling the operation of device 105. In oneembodiment, power converter 135 transforms the terminal voltage ofbattery 130, which is approximately between 2 Volts and 3.25 Volts, intoa 750 Volt defibrillation output energy pulse stored on thedefibrillation output capacitor 140. In another embodiment, powerconverter 135 transforms the terminal voltage of two series-coupledbatteries, which is approximately between 4 Volts and 6.25 Volts, intothe 750 Volt defibrillation output energy pulse stored on thedefibrillation output capacitor 140.

In the illustrated embodiment, various electrical components, includingboth discrete components and monolithic integrated circuits (e.g.,portions of power converter 135 and controller 145), within device 105are located on at least one multilayer hybrid substrate circuit board150 (also referred to as a “circuit board,” “board,” “hybrid,” or“substrate.”) In one embodiment, discrete surface mount tantalumcapacitors 155A-E are mounted to substrate 150, as discussed below. Inone example, tantalum capacitors 155A-E are power supply stabilizationcapacitors that interface with regulated power supply circuits incontroller 145. However, the present invention also includes any othercircuits using discrete capacitors mounted on substrate 150.

FIG. 2A is a schematic diagram of a perspective view illustratinggenerally one embodiment of a conventional arrangement of surface mountcapacitors 155A-E on substrate 150. The surface mount capacitors 155each have a solid rectangular shape, as illustrated in FIG. 2A. In oneembodiment, by way of example, but not by way of limitation, capacitors155 include a plurality (e.g., five) tantalum capacitors. A base of eachcapacitor 155 is mounted to substrate 150 such that conductiveelectrical contacts 200A-B, at opposing ends of the bases and extendingpartially along the corresponding sides, make physical and electricalcontact with corresponding conductive electrical contact landing pads205A-B on the surface of substrate 150. In one embodiment, mountingcapacitors 155 to substrate 150 includes soldering electrical contacts200A-B on the capacitors to corresponding pads 205A-B on substrate 205.

As seen in FIG. 2A, the typical low-profile (i.e., having a smallvertical dimension 210), oblong solid rectangular shape of surface mounttantalum capacitors 155 results in capacitors 155 occupying considerablearea on the surface of substrate 150. Pads 205 require the use of evenmore space on substrate 105. Moreover, pad-to-pad spacing requirementsare imposed in order to ensure electrical isolation between pads 205after capacitors 155 are soldered or otherwise mounted to substrate 150.This further increases the space occupied by the capacitors 155 onsubstrate 150. The small vertical dimension 210 results in wasted spacewithin device 150 when other higher-profile components (e.g., a toroidalcoil, having a larger vertical dimension, used in power converter 135)are also mounted on substrate 150.

FIG. 2B is a schematic diagram, taken along the cutline 2B—2B of FIG.2A, that illustrates generally a cross-sectional view of one embodimentof a capacitor 155. In FIG. 2B, contacts 200A-B extend along the base210 of capacitor 155, and also partially along the corresponding firstend 215A and second end 215B of the capacitor 155 before entering theinterior of capacitor 155 for making contact to its anode and cathoderegions.

One aspect of the present invention provides more efficient utilizationof the surface area of substrate 150 than is shown in FIGS. 2A and 2B.This is accomplished by disposing capacitors 155 vertically on substrate150, in spite of the fact that typical surface mount capacitors 155 haveelectrical contacts 200 only on opposing ends of their bases 210 (i.e.,near first end 215A and second end 215B). The present inventionincludes, among other things, rotating the capacitors 155 to extendlongitudinally outward from substrate 150. This decreases the surfacearea on substrate 150 that is occupied by the capacitors 155, asdiscussed below.

FIGS. 3A, 3B, and 3C are schematic diagrams illustrating generally amulti-capacitor module 300, illustrated in an exterior perspective view(FIG. 3A), a cross-sectional side view (FIG. 3B), taken along thecutline 3B—3B in FIG. 3A, and a bottom view (FIG. 3C), taken along thecutline 3C—3C in FIG. 3B. The dimensions illustrated are by way ofexample only, and not by way of limitation.

In FIG. 3A, a module body 305 forms an approximately solid rectangularshape, and includes a top surface 305A, an open bottom surface 305B, andfour side surfaces extending between top surface 305A and bottom surface305B, thereby defining an open interior portion of module body 305 intowhich capacitors 155 are inserted. According to one aspect of theinvention, bottom surface 305B is mounted to a circuit board such ashybrid substrate 150.

FIG. 3B illustrates a cross-sectional view of multi-capacitor module 300taken along the cutline 3B—3B of FIG. 3A. In FIG. 3B, capacitors 155A-Ehave been inserted into module body 305 through its open bottom surface305B. In the vertical orientation of FIG. 3B, each capacitor 155includes its first end 215A being approximately parallel and proximal tobottom surface 305B of module 300, and its second end 215B beingapproximately parallel and proximal to top surface 305A of module 300.First end 215A and second end 215B are oriented as respective bottom andtop capacitor surfaces in FIG. 3B, and are oriented as side surfaces inthe conventional orientation of FIG. 2B. In FIG. 3B, base 210 isvertically oriented outward from substrate 150. By contrast, in theconventional orientation of the surface mount capacitor 155 illustratedin FIG. 2B, base 210 of capacitor 155 is horizontally-oriented to beapproximately parallel to substrate 150 for conventional mountingthereto. Each contact 200B is located substantially adjacent to the topsurface 305A of the interior portion of module body 305. Each contact200A is located substantially adjacent to the open bottom surface 305B.

First and second ends 215A-B of the capacitors 155 define a height 325therebetween. Each of first and second ends 215A-B are approximatelyrectangular, and define a length 330 and width 335, as illustrated inFIG. 3C. According to one aspect of the invention, capacitor height 325is longer than each of the length 330 and width 335 of the capacitor155. As a result, the plurality of capacitors 155A-E occupies lesssurface area of substrate 150 when the bottom surface 305 of module 300is mounted to substrate 150 than when the bases 210 are mounted directlyto substrate 150 as illustrated in FIGS. 2A and 2B.

FIGS. 3A, 3B, and 3C include at least one-conductor 340 for couplingcontacts 200B on the second ends 215B of the capacitors 155A-E to atleast one landing pad on substrate 150. Contacts 200A of capacitors155A-E are directly coupled (e.g., solder-mounted) to separate or commonlanding pads on substrate 150. FIG. 3B illustrates one embodiment, byway of example, but not by way of limitation, in which the contacts 200Bon each capacitor 155A-E are commonly electrically coupled to substrate150 by a single conductor 340. Conductor 340 extends along the interiorof top surface 305A of module 300, and along a side of module 300 to thebottom surface 305B of module 300 where it is solder-mounted orotherwise coupled to a corresponding landing pad on substrate 150. Whilethose portions of contacts 200B extending along the respective bases 210of the capacitors 155 are ordinarily used for electrically coupling tothe capacitor 155, one embodiment of the present inventionadvantageously allows those portions of contacts 200B extending alongthe respective second ends 215B for electrically coupling externalcircuits to the capacitors 155 via conductor 340.

In one embodiment, a portion of conductor 340 extends along the interiorportion of the top surface 305A of module 300, and along a side ofmodule 300 to the bottom surface 305B of module 300, and optionallyextends at least partially along an opposing side of module 300, asillustrated in FIG. 3B. In another embodiment, a comer of the topsurface 305A is optionally notched, thereby exposing a portion ofconductor 340, as illustrated in FIG. 3A.

FIGS. 3D and 3E are schematic diagrams illustrating generally, by way ofexample, but not by way of limitation, particular configurations ofinterconnecting the capacitors 155. In FIGS. 3D and 3E, capacitors 155are polar, the polarity of capacitors 155 can be interchanged either asshown, or in any other suitable arrangement to meet circuit designrequirements.

FIGS. 4A, 4B, and 4C are schematic diagrams, corresponding generally tothe views illustrated respective FIGS. 3A, 3B, and 3C, of anotherembodiment of the present invention. FIGS. 4A, 4B, and 4C illustrate theuse of multiple conductors 340A and 340B. In this embodiment, by way ofexample, but not by way of limitation, contacts 200B of capacitors155A-B are coupled to a the substrate via conductor 340A. Contacts 200Bof capacitors 155C-E are coupled to the substrate via conductor 340B.Contacts 200A of capacitors 155A-E are directly coupled (e.g.,solder-mounted) to separate or common landing pads; on substrate 150.Additional conductors 340 for individually coupling contacts 200B tosubstrate 150 can also be included (e.g., extending down the same ordifferent sides of module body 305).

FIGS. 4D, 4E, and 4F are schematic diagrams illustrating generally, byway of example, but not by way of limitation, particular configurationsof interconnecting the capacitors 155. In FIGS. 4D-4F, capacitors 155are polar; the polarity of capacitors 155 can be interchanged either asshown, or in any other suitable arrangement to meet circuit designrequirements.

FIGS. 5A and 5B are schematic diagrams illustrating generally respectiveplan views, looking down toward the surface of substrate 150, of onearrangement of conventionally mounted surface mount capacitors 155A-E,having the “footprint” illustrated by FIG. 5A, and another arrangementof the same capacitors 155A-E vertically disposed in module 300,according to the present invention, having the footprint illustrated byFIG. 5B. A comparison of FIGS. 5A and 5B illustrates the dramaticreduction (by a factor of approximately 2/3) in surface area ofsubstrate 150 occupied by the capacitors 155A-E in the arrangement ofFIG. 5B as compared to the conventional arrangement illustrated in FIG.5A.

Reducing the amount of surface area required for mounting capacitors 155to substrate 150 is particularly advantageous when enough space existsin a vertical dimension (outward from the surface of substrate 150) toaccommodate the taller vertically-oriented surface mount capacitors 155carried in multi-capacitor module 300. For example, as discussed above,when substrate 150 is already populated with higher-profile discretecomponents (e.g., a toroidal coil), such space is available in adirection outward from the surface of substrate 150. Other designchoices may also result in space being available in a direction outwardfrom the surface of substrate 150. The present invention allows suchspace to be utilized by capacitors 155 rather than remaining empty. Thisprovides more efficient use of the volume within an implantable device105, reducing its size, or alternatively, increasing its implantedlongevity by accommodating a larger battery 130.

CONCLUSION

Thus, the present invention provides, among other things, amulti-capacitor module for carrying vertically-oriented surface mountcapacitors. The module provides at least one conductor for coupling tothe substrate capacitor terminals that are distal thereto. The moduleoccupies less space, when mounted to a circuit board substrate, thanindividually mounting the bases of the surface mount capacitors to thesubstrate. This allows more efficient use of volume within animplantable cardiac rhythm management device, reducing its size, oralternatively, increasing its implanted longevity.

It is to be understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reviewing the abovedescription. The scope of the invention should, therefore, be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

What is claimed is:
 1. A cardiac rhythm management system comprising: ahousing; a battery within the housing; a hybrid circuit board substrate,within the housing, the substrate including multiple conductive andinsulating layers; a multi-capacitor module including a module bodyhaving opposing top and bottom module surfaces, the module bodyincluding electrical terminals that are electrically coupled to thesubstrate, the bottom module surface being mounted to the substrate,wherein the module body includes greater than two electrical terminals;and a plurality of capacitors carried within the module and connected tothe greater than two electrical terminals.
 2. The system of claim 1, inwhich the capacitors are surface mount tantalum capacitors.
 3. Thecardiac rhythm management system of claim 1, wherein the module carriesfive capacitors.
 4. The cardiac rhythm management system of claim 1,wherein the hybrid circuit board substrate is populated withhigher-profile discrete components that protrude in a direction outwardfrom the circuit board surface.
 5. The cardiac rhythm management systemof claim 1, wherein a first capacitor terminal of at least one of theplurality of capacitors are solder-mounted to a common-landing pad onthe circuit board.
 6. The system of claim 1, wherein one of the electricterminals is common to a plurality of capacitors, and wherein each ofthe plurality of capacitors includes a distinct terminal that isseparate from the one common electric terminal.
 7. The system of claim7, wherein one of the electric terminals is common to all of thecapacitors in the module.
 8. The system of claim 1, wherein themulti-capacitor module includes a first group of capacitors and a secondgroup of capacitors, wherein the first group has a first commonterminal, and wherein the second group has a second common terminal. 9.A cardiac rhythm management system, comprising: a housing; a batterywithin the housing; a hybrid circuit board substrate, within thehousing, the substrate including multiple conductive and insulatinglayers; a multi-capacitor module including a module body having opposingtop and bottom module surfaces, the module body including electricalterminals that are electrically coupled to the substrate, the bottommodule surface being mounted to the substrate; a plurality of capacitorscarried within the module; and in which each capacitor is electricallycoupled to the terminals on the module body, and each capacitor includesa capacitor body having opposing first and second capacitor endsdefining a capacitor height there between, one of the first and secondcapacitor ends defining a length and a width of the capacitor, whereinthe first capacitor end is approximately adjacent to the substrate andthe capacitor height is longer than each of the length and the width ofthe capacitor.
 10. The cardiac rhythm management system of claim 9,wherein the first capacitor ends are substantially adjacent to thebottom module surface and the second capacitor ends are substantiallyadjacent to the top module surface.
 11. The system of claim 9, in whicheach capacitor includes: a first capacitor terminal at the firstcapacitor end; and a second capacitor terminal at the second capacitorend.
 12. The system of claim 11, in which each capacitor includes a baseextending between the first and second capacitor ends, the firstcapacitor terminal extends partially along the base proximal to thefirst capacitor end, the second capacitor terminal extends partiallyalong the base proximal to the second capacitor end.
 13. The system ofclaim 12, in which the bottom module surface occupies less mounting areaon the surface of the substrate than areas of the bases summed over theplurality of the capacitors.
 14. The system of claim 11, in which thefirst capacitor terminals provide ones of the terminals, on the modulebody, that are electrically coupled to the substrate.
 15. The cardiacrhythm management system of claim 11, further comprising a firstconductor extends along a first portion of the interior portion of thetop module surface and being coupled to a first plurality of the secondcapacitor terminals, the first conductor also extends along the interiorportion of a first side module surface and extends to a first portion ofthe bottom module surface and provides an electrical terminal forconnecting the second capacitor terminals to an external circuit; andwherein further a second conductor extending along a second portion ofthe interior portion of the top module surface and being coupled to asecond plurality of the second capacitor terminals, the second conductoralso extends along the interior portion of a second side module surfaceand extends to a second portion of the bottom module surface andprovides an electrical terminal for connecting the second capacitorterminals to an external circuit.
 16. The cardiac rhythm managementsystem of claim 11, further comprising a plurality of additionalconductors to individually and electronically couple the secondcapacitor terminals, at the second capacitor ends, to the circuit board.17. The system of claim 11, further including at least one conductorthat is electrically coupled to at least one of the second capacitorterminals, the conductor extending to the bottom surface of the moduleand providing one of the terminals, on the module body, that iselectrically coupled to the substrate.
 18. The cardiac rhythm managementsystem of claim 17, wherein the conductor extends along an interiorportion of the top module surface and further extends along an interiorportion of a side module surface to the bottom surface of the module.19. The cardiac rhythm management system of claim 17, wherein theconductor is located substantially in the interior portion of themodule.
 20. The cardiac rhythm management system of claim 19, whereinthe corner of the top module surface is notched such that a portion ofthe conductor is exposed.
 21. The cardiac rhythm management system ofclaim 20, wherein the exposed portion of the conductor is electricallycoupled to external circuitry.
 22. A cardiac rhythm management system,comprising: a housing; a battery within the housing; a hybrid circuitboard substrate, within the housing, the substrate including multipleconductive and insulating layers; a multi-capacitor module including amodule body having opposing, top and bottom module surfaces, the modulebody including electrical terminals that are electrically coupled to thesubstrate, the bottom module surface being mounted to the substrate; aplurality of capacitors carried within the module; and in which thebottom module surface is open for accessing an interior of the modulebody.
 23. A method of making a cardiac rhythm management system, themethod comprising: forming a housing; disposing a battery within thehousing; disposing within the housing a hybrid circuit board substrateincluding multiple conductive and insulating layers; mounting on thesubstrate a multi-capacitor module including a module body havingopposing top and bottom module surfaces; disposing a plurality ofcapacitors within the module; and connecting more than two electricalterminals to the plurality of capacitors.
 24. The method of claim 23, inwhich disposing a plurality of capacitors includes disposing a pluralityof surface mount tantalum capacitors within the module.
 25. The methodof claim 23, further comprising disposing five capacitors within themodule.
 26. The method of claim 23, wherein disposing within the housinga hybrid circuit board substrate includes populating the hybrid circuitboard substrate with higher-profile discrete components that protrude ina direction outward from the circuit board surface.
 27. A cardiac rhythmmanagement system comprising: a housing; a battery within the housing; ahybrid circuit board substrate, within the housing, the substrateincluding multiple conductive and insulating layers; a multi-capacitormodule including a module body having opposing top and bottom modulesurfaces, the module body including electrical terminals that areelectrically coupled to the substrate, the bottom module surface beingmounted to the substrate; and a plurality of capacitors carried withinthe module, wherein the plurality of capacitors are vertically disposedin a row within the module.
 28. A cardiac rhythm management system,comprising: a housing; a battery within the housing; a hybrid circuitboard substrate, within the housing, the substrate including multipleconductive and insulating layers; a multi-capacitor module including amodule body having opposing top and bottom module surfaces, the modulebody including electrical terminals that are electrically coupled to thesubstrate, the bottom module surface being mounted to the substrate; aplurality of capacitors carried within the module; and wherein themulti-capacitor module is mounted upon the hybrid circuit boardsubstrate at the bottom module surface, the hybrid circuit board beingelectronically coupled to a portion of a conductor at the bottom modulesurface and also electrically coupled to a first capacitor terminal atthe bottom module surface.
 29. A cardiac rhythm management system,comprising: a housing; a battery within the housing; a hybrid circuitboard substrate, within the housing, the substrate including multipleconductive and insulating layers; a multi-capacitor module including amodule body having opposing top and bottom module surfaces, the modulebody including electrical terminals that are electrically coupled to thesubstrate, the bottom module surface being mounted to the substrate; aplurality of capacitors carried within the module; and wherein themodule body includes a notched corner between the top module surface andone of a plurality of side module surfaces.
 30. A method of making acardiac rhythm management system, the method comprising: forming ahousing; disposing a battery within the housing; disposing within thehousing a hybrid circuit board substrate including multiple conductiveand insulating layers; mounting on the substrate a multi-capacitormodule including a module body having opposing top and bottom modulesurfaces; and disposing a plurality of capacitors within the module,wherein disposing a plurality of capacitors includes disposing thecapacitors vertically in a row within the module.
 31. A method of makinga cardiac rhythm management system, the method comprising: forming ahousing; disposing a battery within the housing; disposing within thehousing a hybrid circuit board substrate including multiple conductiveand insulating layers; mounting on the substrate a multi-capacitormodule including a module body having opposing top and bottom modulesurfaces; disposing a plurality of capacitors within the module; anddisposing a conductor substantially in the interior portion of themodule, the conductor extending along the interior portion of the topmodule surface and being electrically coupled to each of the secondcapacitor terminals, the conductor also extending along the interiorportion of one of the side module surfaces and extending to the bottommodule surface and providing an electrical terminal for connecting thesecond capacitor terminals to an external circuit.
 32. A method ofmaking a cardiac rhythm management system, the method comprising:forming a housing; disposing a battery within the housing; disposingwithin the housing a hybrid circuit board substrate including multipleconductive and insulating layers; mounting on the substrate amulti-capacitor module including a module body having opposing top andbottom module surfaces; disposing a plurality of capacitors within themodule; and disposing a plurality of conductors located substantially inthe interior portion of the module; wherein a first conductor extendsalong a first portion of the interior portion of the top module surfaceand being coupled to a first plurality of the second capacitorterminals, the first conductor also extends along the interior portionof a first side module surface and extends to a first portion of thebottom module surface and provides an electrical terminal for connectingthe second capacitor terminals to an external circuit; wherein further asecond conductor extends along a second portion of the interior portionof the top module surface and being coupled to a second plurality of thesecond capacitor terminals, the second conductor also extends along theinterior portion of a second side module surface and extends to a secondportion of the bottom module surface and provides an electrical terminalfor connecting the second capacitor terminals to an external circuit.33. A method of making a cardiac rhythm management system, the methodcomprising: forming a housing; disposing a battery within the housing;disposing within the housing a hybrid circuit board substrate includingmultiple conductive and insulating layers; mounting on the substrate amulti-capacitor module including a module body having opposing top andbottom module surfaces; disposing a plurality of capacitors within themodule; and electrically coupling the portion of the conductor at thebottom module surface and at least one of the plurality of capacitorswithin the module to the hybrid circuit board substrate.
 34. A cardiacrhythm management system comprising: a housing; a battery within thehousing; a hybrid circuit board substrate, within the housing, thesubstrate including multiple conductive and insulating layers; amulti-capacitor module including a module body having opposing top andbottom module surfaces, the module body including electrical terminalsthat are electrically coupled to the substrate, the bottom modulesurface being mounted to the substrate; and a plurality of capacitorscarried within the module, wherein the multi-capacitor module includes Ncapacitors and the number of electric terminals are N+1.
 35. A cardiacrhythm management system comprising: a housing; a battery within thehousing; a hybrid circuit board substrate, within the housing, thesubstrate including multiple conductive and insulating layers; amulti-capacitor module including a module body having opposing top andbottom module surfaces, the module body including electrical terminalsthat are electrically coupled to the substrate, the bottom modulesurface being mounted to the substrate; and a plurality of capacitorscarried within the module, wherein the multi-capacitor module includes Ncapacitors and the number of electric terminals are N+2.
 36. A cardiacrhythm management system comprising: a housing; a battery within thehousing; a hybrid circuit board substrate, within the housing, thesubstrate including multiple conductive and insulating layers; amulti-capacitor module including a module body having opposing top andbottom module surfaces, the module body including electrical terminalsthat are electrically coupled to the substrate, the bottom modulesurface being mounted to the substrate; a plurality of capacitorscarried within the module; wherein the multi-capacitor module includes afirst group of capacitors and a second group of capacitors, wherein thefirst group has a first common terminal, and wherein the second grouphas a second common terminal; and wherein each of the first group ofcapacitors includes an individual electric terminal that is separatefrom the first common terminal.
 37. The system of claim 36, wherein eachof the second group of capacitors includes an individual electricterminal that is separate from the second common terminal.